The less injury you cause to a living plant the better.
Does this work with any other fruit or vegetable? Does 'killing' lettuce make it taste bad? I suppose you could eat it off the ground like a rabbit. A chopped up tomato or apple tastes as good as a whole one. Isn't death by thirst an injury too? There's a big difference between a disease, for instance mites, that cover a healthy vegetative plant and suck it's juice over months and cutting a plant and hanging it.
The idea of 'slow killing' a plant isn't a new one. The idea of girdling a plant, cutting off it's supply of water and food from the roots by scarring the stem. This is the same as depriving a plant of water, which is the same as depriving a plant of it's roots by harvesting. I've had plants girdled by boytritis. It caused the plant to mature much faster but didn't improve the quality. I can see how it could be useful in certain situations.
The biggest problem with murdering your plants by thirst is the sun. It's going to do a lot of damage to the flowers, to the cannabinoids as the plant dies. An indoor grower can avoid this by putting the plant in a dark room to starve and it's been tried. Some growers like giving a plant 24 or 48 hours of darkness, without water or whatever. Hell, build your own plant torture chamber, whatever gets you off.
If you're harvesting your plants at the right time, when it's entered senescence and peak potency, there's no need for all this shit. When a plant naturally reaches the end of it's life it's ready. Growers try all sorts of tricks but there's a reason people do things the way they do. The less the terpenes and cannabinoids degrade the better.
Harvesting your plant at the right time then hanging it in a dark room at a cool dry temperature for a couple weeks is the best thing you can do for your ganja. I've smoked ganja that's been cured and fucked with all sorts of different ways, dried killed and whatever, and some of it was okay. Some of it got me baked. None of it was as good as the stuff that was treated right.
You can always run a test experiment. Two identical clones, one harvested and one left to dry and wither. I've done this myself by accident, harvested most of a plant, then forgotten about he last part and found the dried out lower half a month later. The dried out part was harsh and the cannabinoids had degenerated a bit but it still got me baked. The stuff I'd hung in the dark, cured properly, and kept in a jar was much better.